HP 85688 Guide

Performance Tests and
Adjustments Manual
HP 85688 Spectrum Analyzer
_-
Fi
HEWLETT
PACKARD
HP Part No. 08588-80115
Printed in USA June 1993

COPYRIGHT AND DISCLAIMER NOTICE
Copyright - Agilent Technologies, Inc. Reproduced with the permission of Agilent
Technologies Inc. Agilent Technologies, Inc. makes no warranty of any kind with regard
to this material including, but not limited to, the implied warranties of merchantability
and fitness for aparticular purpose. Agilent Technologies, Inc. is not liable for errors
contained herein or for incidental or consequential damages in connection with the
furnishing, performance, or use of this material or data.

@Copyright Hewlett-Packard Company 1993
All Rights Reserved. Reproduction, adaptation, or translation without prior written
permission is prohibited, except as allowed under the copyright laws.
1212 Valley House Drive, Rohnert Park, CA 94928-4999, USA

Certification
Hewlett-Packard Company certifies that this product met its published specifications at the
time of shipment from the factory. Hewlett-Packard further certifies that its calibration
measurements are traceable to the United States National Institute of Standards and
Technology, to the extent allowed by the Institute’s calibration facility, and to the calibration
facilities of other International Standards Organization members.
Warranty
This Hewlett-Packard instrument product is warranted against defects in material and
workmanship for a period of one year from date of shipment. During the warranty period,
Hewlett-Packard Company will, at its option, either repair or replace products which prove to
be defective.
For warranty service or repair, this product must be returned to a service facility designated
by Hewlett-Packard. Buyer shall prepay shipping charges to Hewlett-Packard and
Hewlett-Packard shall pay shipping charges to return the product to Buyer. However, Buyer
shall pay all shipping charges, duties, and taxes for products returned to Hewlett-Packard
from another country.
Hewlett-Packard warrants that its software and firmware designated by Hewlett-Packard for
use with an instrument will execute its programming instructions when properly installed on
that instrument. Hewlett-Packard does not warrant that the operation of the instrument, or
software, or firmware will be uninterrupted or error-free.
LIMITATION OF WARRANTY
The foregoing warranty shall not apply to defects resulting from improper or inadequate
maintenance by Buyer, Buyer-supplied software or interfacing, unauthorized modification or
misuse, operation outside of the environmental specifications for the product, or improper
site preparation or maintenance.
NO OTHER WARRANTY IS EXPRESSED OR IMPLIED. HEWLETT-PACKARD
SPECIFICALLY DISCLAIMS THE IMPLIED WARRANTIES OF MERCHANTABILITY
AND FITNESS FOR A PARTICULAR PURPOSE.
EXCLUSIVE REMEDIES
THE REMEDIES PROVIDED HEREIN ARE BUYER’S SOLE AND EXCLUSIVE
REMEDIES. HEWLETT-PACKARD SHALL NOT BE LIABLE FOR ANY DIRECT,
INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, WHETHER
BASED ON CONTRACT, TORT, OR ANY OTHER LEGAL THEORY.
Assistance
Product maintenance agreements and other customer assistance agreements are available for
Hewlett-Packard products.
For any assistance, contact your nearest Hewlett-Packard Sales and Service Ofice.

Safety Symbols
The following safety symbols are used throughout this manual. Familiarize yourself with each
of the symbols and its meaning before operating this instrument.
Caution
The caution sign denotes a hazard. It calls attention to a procedure which,
if not correctly performed or adhered to, could result in damage to or
destruction of the instrument. Do not proceed beyond a caution sign until the
indicated conditions are fully understood and met.
Warning
The warning sign denotes a hazard. It calls attention to a procedure which,
if not correctly performed or adhered to, could result in injury or loss of life.
Do not proceed beyond a warning sign until the indicated conditions are fully
understood and met.
General Safety Considerations
Warning
Before this instrument is switched on, make sure it has been properly grounded
through the protective conductor of the ac power cable to a socket outlet
provided with protective earth contact.
Any interruption of the protective (grounding) conductor, inside or outside
the instrument, or disconnection of the protective earth terminal can result in
personal injury.
Warning
There are many points in the instrument which can, if contacted, cause personal
injury. Be extremely careful.
Any adjustments or service procedures that require operation of the instrument
with protective covers removed should be performed only by trained service
personnel.
Caution
Before this instrument is switched on, make sure its primary power circuitry
has been adapted to the voltage of the ac power source.
Failure to set the ac power input to the correct voltage could cause damage to
the instrument when the ac power cable is plugged in.
iv

-
HP 8568B Spectrum Analyzer Documentation Outline
Included with the HP Model 8568B Spectrum Analyzer are three manuals: the Installation
and Verification Manual, the Operating and Programming Manual, and the Performance Tests
and Adjustments Manual.
HP 85688 Installation and Verification Manual
General information, installation, specifications, characteristics, and operation verification.
HP 85688 Operating and Programming Manual
Manual and remote operation, including complete syntax and command description.
Accompanying this manual is the separate, pocket-sized Quick Reference Guide.
HP 85688 Performance Tests and Adjustments Manual
Electrical performance tests and adjustment procedures.
HP 856808 RF Section Troubleshooting and Repair Manual
RF Section service information.
HP 85662A IF-Display Section Troubleshooting and Repair Manual
IF-Display Section service information.
-

Contents
1. General Information
Introduction .............................
Instruments Covered by this Manual .................
Operation Verification ........................
Option 462 Instruments .......................
Option 857 Instruments .......................
2. Performance Tests
Introduction .............................
Verification of Specifications .....................
Calibration Cycle ..........................
Equipment Required ........................
Test Record ............................
1. Center Frequency Readout Accuracy Test .............
2. Frequency Span Accuracy Test ..................
3. Sweep Time Accuracy Test (220 ms) ...............
4. Resolution Bandwidth Accuracy Test ...............
5. Resolution Bandwidth Selectivity Test ..............
6. Resolution Bandwidth Switching Uncertainty Test .........
7. Input Attenuator Switching Uncertainty Test ...........
8. Frequency Response Test ....................
9. RF Gain Uncertainty Test ....................
10. IF Gain Uncertainty Test ....................
11. Log Scale Switching Uncertainty Test ..............
12. Amplitude Fidelity Test ....................
13. Average Noise Level Test ....................
14. Residual Responses Test ....................
15. Spurious Responses Test ....................
16. Residual FM Test .......................
17. Line-Related Sidebands Tests ..................
18. Calibrator Amplitude Accuracy Test ...............
19. Fast Sweep Time Accuracy Test (~20 ms) ............
20. 1st LO Output Amplitude Test .................
21. Frequency Reference Error Test .................
Performance Test Record .......................
Test 1. Center Frequency Readout Accuracy Test ............
Test 2. Frequency Span Accuracy Test ................
Test 3. Sweep Time Accuracy ....................
Test 4. Resolution Bandwidth Accuracy ................
Test 5. Resolution Bandwidth Selectivity ...............
Test 6. Resolution Bandwidth Switching Uncertainty Test ........
Test 7. Input Attenuator Switching Uncertainty Test ..........
l-l
l-l
l-2
1-2
l-2
2-1
2-l
2-l
2-2
2-2
2-4
2-7
2-10
2-14
2-16
2-19
2-21
2-23
2-33
2-35
2-41
2-43
2-47
2-49
2-52
2-58
2-61
2-63
2-64
2-67
2-68
2-71
2-72
2-73
2-74
2-75
2-76
2-77
2-78
Contents-l

Test 8. Frequency Response Test ...................
Test 9. RF Gain Uncertainty Test ..................
Test 10. IF Gain Uncertainty Test ..................
Test 11. Log Scale Switching Uncertainty Test .............
Test 12. Amplitude Fidelity Test ...................
Test 13. Average Noise Level Test ..................
Test 14. Residual Responses Test ...................
Test 15. Spurious Responses Test ...................
Test 16. Residual FM Test ......................
Test 17. Line-Related Sidebands Test .................
Test 18. Calibrator Amplitude Accuracy Test .............
Test 19. Fast Sweep Time Accuracy Test (<20 ms) ...........
Test 20. 1st LO Output Amplitude Test ................
Test 21. Frequency Reference Error Test ................
3. Adjustments
Introduction .............................
Safety Considerations .........................
Equipment Required .........................
Adjustment Tools ...........................
Factory-Selected Components ......................
Related Adjustments .........................
Location of Test Points and Adjustments ................
1. Low-Voltage Power Supply Adjustments ...............
2. High-Voltage Adjustment (SN 3001A and Below) ...........
2. High-Voltage Adjustment (SN 3004A and Above) ...........
3. Preliminary Display Adjustments (SN 3001A and Below) .......
3. Preliminary Display Adjustments (SN 3004A and Above) .......
4. Final Display Adjustments (SN 3001A and Below) ..........
4. Final Display Adjustments (SN 3004A and Above) ..........
5. Log Amplifier Adjustments ....................
6. Video Processor Adjustments ...................
7. 3 MHz Bandwidth Filter Adjustments ...............
8. 21.4 MHz Bandwidth Filter Adjustments ..............
9. 3 dB Bandwidth Adjustments ...................
10. Step Gain and 18.4 MHz Local Oscillator Adjustments ........
11. Down/Up Converter Adjustments .................
12. Time Base Adjustment (SN 2840A and Below, also 3217A05568 and
Above) .............................
12. Time Base Adjustment (SN 2848A to 3217A05567) .........
13. 20 MHz Reference Adjustments ..................
14. 249 MHz Phase Lock Oscillator Adjustments ............
15. 275 MHz Phase Lock Oscillator Adjustment ............
16. Second IF Amplifier and Third Converter Adjustment ........
17. Pilot Second IF Amplifier Adjustments ...............
18. Frequency Control Adjustments ..................
19. Second Converter Adjustments ..................
20. 50 MHz Voltage-Tuned Oscillator Adjustments ...........
21. Slope Compensation Adjustments .................
22. Comb Generator Adjustments ...................
23. Analog-To-Digital Converter Adjustments .............
2-79
2-80
2-81
2-84
2-85
2-86
2-87
2-88
2-89
2-90
2-91
2-92
2-93
2-94
3-l
3-2
3-2
3-2
3-4
3-4
3-4
3-25
3-29
3-39
3-45
3-53
3-61
3-63
3-67
3-72
3-75
3-80
3-88
3-91
3-97
3-101
3-105
3-109
3-114
3-117
3-119
3-124
3-127
-3-131
3-138
3-142
3-146
3-150
Contents-2

24. Track and Hold Adjustments ................... 3-153
25. Digital Storage Display Adjustments ................ 3-156
Low-Noise DC Supply ........................ 3-161
Crystal Filter Bypass Network Configuration .............. 3-163
4. Option 462
Introduction .............................
4. Impulse and Resolution Bandwidth Accuracy Test ..........
5. Impulse and Resolution Bandwidth Selectivity Test ..........
6. Impulse and Resolution Bandwidth Switching Uncertainty Test ....
HP 8568B Option 462 Performance Test Record ............
9. Impulse Bandwidth Adjustments ..................
5. Option 857
Introduction .............................
12. Option 857 Amplitude Fidelity Test ................
Performance Test Record .......................
Test 12. Amplitude Fidelity Test ...................
6. Major Assembly and Component Locations
IF-Display Section Figure Index . . . . . . . . . . . . . . . . . . . .
RF Section Figure Index . . . . . . . . . . . . . . . . . . . . . . . .
4-1
4-2
4-8
4-11
4-13
4-17
5-1
5-2
5-7
5-8
6-1
6-2
Contents-3

Figures
l-l. Service Accessories, HP Part Number 08568-60001 ...........
2-l. Center Frequency Accuracy Test Setup ................
2-2. Center Frequency Readout Error Measurement .............
2-3. Frequency Span Accuracy Test Setup .................
2-4. Sweep Time Accuracy Test Setup ...................
2-5. Penlift Output Signal ........................
2-6. Resolution Bandwidth Measurement ..................
2-7. 60 dB Bandwidth Measurement ....................
2-8. Bandwidth Switching Uncertainty Measurement ............
2-9. Attenuator Switching Uncertainty Test Setup ..............
2-10. Attenuator Switching Uncertainty Measurement ............
2-11. Frequency Response Test Setup (20 MHz to 1.5 GHz) ..........
2-12. Frequency Response Measurement (20 MHz to 1.5 GHz) .........
2-13. Frequency Response Test Setup (100 kHz to 20 MHz) ..........
2-14. Frequency Response Measurement (100 kHz to 20 MHz) .........
2-15. Frequency Response Test Setup (100 Hz to 100 kHz) ..........
2-16. RF Gain Uncertainty Measurement ..................
2-17. IF Gain Uncertainty Test Setup ...................
2-18. IF Gain Uncertainty Measurement ..................
2-19. IF Gain Uncertainty Measurement (2 dB) ...............
2-20. Log Scale Switching Uncertainty Measurement .............
2-21. Amplitude Fidelity Test Setup ....................
2-22. Amplitude Fidelity Measurement ...................
2-23. Average Noise Level Measurement ..................
2-24. Residual Responses Measurement ...................
2-25. Harmonic Distortion Test Setup ...................
2-26. Intermodulation Distortion Test Setup .................
2-27. Intermodulation Distortion Products .................
2-28. Bandwidth Filter Slope Measurement .................
2-29. Slope Detected Residual FM .....................
2-30. Peak-to-Peak Amplitude Measurement .................
2-31. Line Related Sidebands Measurement .................
2-32. Calibrator Amplitude Accuracy Test Setup ...............
2-33. Fast Sweep Time Accuracy (<20 ms Test Setup) ............
2-34. Fast Sweep Time Measurement (<20 ms) ...............
2-35. 1st LO Output Amplitude Test Setup .................
2-36. Frequency Reference Test Setup ...................
3-l. Low-Voltage Power Supply Adjustments Setup .............
3-2. IF-Display Section Low-Voltage Adjustments (SN 3001A and Below) ...
3-3. IF-Display Section Low-Voltage Adjustments (SN 3004A and Above) ...
3-4. Location of RF Section Low-Voltage Adjustments ............
3-5. High Voltage Adjustment Setup ...................
Contents-4
l-8
2-4
2-5
2-8
2-10
2-12
2-15
2-17
2-20
2-21
2-22
2-23
2-25
2-27
2-28
2-29
2-34
2-35
2-37
2-38
2-42
2-43
2-45
2-48
2-50
2-53
2-55
2-56
2-59
2-59
2-60
2-62
2-63
2-64
2-66
2-67
2-69
3-25
3-26
3-27
3-28
3-30

- 3-6. Location of High Voltage Adjustments .................
3-7. Location of Label and Test Point ...................
3-8. Location of AlA Components ....................
3-9. CRT Cut-Off Voltage ........................
3-10. Waveform at AlA3TP5 .......................
3-11. Discharging the CRT Post-Accelerator Cable ..............
3-12. High Voltage Adjustment Setup ...................
3-13. Location of High Voltage Adjustments .................
3-14. Location of AlA Label and Test Point ................
3-15. Discharging the CRT Post-Accelerator Cable ..............
3-16. Preliminary Display Adjustments Setup ................
3-17. Location of AlA2, AlA4, AlA5, and A3A2 ..............
3-18. AlA2, AlA4, and AlA Adjustment Locations .............
3-19. X-l- and X- Waveforms .......................
3-20. Composite X Deflection Waveform ..................
3-21. Rise and Fall Times and Overshoot Adjustment Waveform ........
3-22. 5OV,, Signal ............................
3-23. Preliminary Display Adjustments Setup ................
3-24. Location of AlA and A3A2 .....................
3-25. AlA Adjustment Locations ......................
3-26. X+ and X- Waveforms .......................
3-27. Composite X Deflection Waveform ..................
3-28. Rise and Fall Times and Overshoot Adjustment Waveform ........
3-29. 5OV,, Signal ............................
3-30. Location of Final Display Adjustments on AlA2, AlA4, and AlA ....
3-31. Final Display Adjustments Setup ...................
3-32. Location of Final Display Adjustments on AlA ............
3-33. Log Amplifier Adjustments Setup ...................
3-34. Location of Log Amplifier Adjustments ................
3-35. Video Processor Adjustments Setup ..................
3-36. Location of Video Processor Adjustments ...............
3-37. 3 MHz Bandwidth Filter Adjustments Setup ..............
3-38. Location of Center, Symmetry, and 10 Hz Amplitude Adjustments ....
3-39. Location of 3 MHz Peak Adjustments .................
3-40. 21.4 MHz Bandwidth Filter Adjustments Setup ............
3-41. Location of A4A4 21.4 MHz LC Filter Adjustments ...........
3-42. Location of A4A4 21.4 MHz Crystal Filter Adjustments .........
3-43. Location of A4A8 21.4 MHz LC Filter and Attenuation Adjustments ...
3-44. Location of A4A8 21.4 MHz Crystal Filter Adjustments .........
3-45. Location of 3 dB Bandwidth Adjustments ...............
3-46. Step Gain and 18.4 MHz Local Oscillator Adjustments Setup .......
3-47. Location of IF Gain Adjustment ...................
3-48. Location of 10 dB Gain Step Adjustments ...............
3-49. Location of .1 dB Gain Step, 18.4 MHz LO, and +lOV Adjustments ....
3-50. Down/Up Converter Adjustments Setup ................
3-51. Location of Down/Up Converter Adjustments .............
3-52. Time Base Adjustment Setup .....................
3-53. Location of A27Al Adjustment ....................
3-54. Time Base Adjustment Setup .....................
3-55. Location of A27A2 Adjustment ....................
3-56. 20 MHz Reference Adjustments Setup .................
3-31
3-32
3-34
3-35
3-36
3-38
3-40
3-41
3-42
3-44
3-46
3-47
3-47
3-48
3-49
3-50
3-51
3-54
3-55
3-55
3-56
3-57
3-58
3-59
3-62
3-63
3-64
3-67
3-69
3-72
3-73
3-75
3-77
3-78
3-80
3-82
3-83
3-84
3-85
3-89
3-91
3-93
3-94
3-95
3-97
3-99
3-101
3-104
3-105
3-108
3-109
Contents-5

3-57. Location of 20 MHz Reference Adjustments ..............
3-58. Typical Signal at A16TP3 ......................
3-59. 249 MHz Phase Lock Oscillator Adjustments Setup ...........
3-60. Location of 249 MHz Phase Lock Oscillator Adjustments ........
3-61. 275 MHz Phase Lock Oscillator Adjustment Setup ...........
3-62. Location of 275 MHz PLO Adjustment ................
3-63. Second IF Amplifier Adjustments Setup ................
3-64. Location of 301.4 MHz BPF and 280 MHz AMPTD Adjustments .....
3-65. 301.4 MHz Bandpass Filter Adjustment Waveform ...........
3-66. Minimum Image Response at 258.4 MHz ................
3-67. Pilot Second IF Amplifier Adjustments Setup ..............
3-68. Location of 269 MHz Bandpass Filter Adjustments ...........
3-69. 269 MHz Bandpass Filter Adjustments Waveforms ...........
3-70. Frequency Control Adjustments Setup .................
3-71. Location of Frequency Control Adjustments ..............
3-72. Second Converter Adjustments Setup .................
3-73. Location of Second Converter Adjustments ...............
3-74. Typical PILOT 2ND IF Bandpass (SHIFT r) ..............
3-75. Typical PILOT 2ND IF Bandpass (SHIFT 1) ..............
3-76. Typical Bandpass (SHIFT r) .....................
3-77. Typical Bandpass (SHIFT 1) .....................
3-78. 50 MHz Voltage-Tuned Oscillator Adjustments Setup ..........
3-79. Location of 50 MHz VT0 Adjustments ................
3-80. Slope Compensation Adjustment Setup ................
3-81. Location of A22R66 TILT Adjustment .................
3-82. Slope Compensation Adjustment Waveforms ..............
3-83. Location of Comb Generator Adjustments ...............
3-84. Comb Teeth Display .........................
3-85. Analog-To-Digital Converter Adjustments Setup ............
3-86. Location of Analog-To-Digital Converter Adjustments ..........
3-87. Track and Hold Adjustments Setup ..................
3-88. Location of Track and Hold Adjustments ................
3-89. Digital Storage Display Adjustments Setup ...............
3-90. Location of Digital Storage Display Adjustments ............
3-91. Sample and Hold Balance Adjustment Waveforms ............
3-92. Waveform Before Adjustment .....................
3-93. Low-Noise DC Supply ........................
3-94. Crystal Filter Bypass Network Configurations .............
4-l. Impulse Bandwidth Test Setup ....................
4-2. 6 dB Resolution Bandwidth Measurement ...............
4-3. 60 dB Bandwidth Measurement ....................
4-4. Bandwidth Switching Uncertainty Measurement ............
4-5. Location of Bandwidth Adjustments ..................
5-l. Option 857 Amplitude Fidelity Test Setup ...............
6-l. RF Section, Top View ........................
6-2. RF Section, Front View .......................
6-3. RF Section, Bottom View ......................
6-4. IF Section, Top View (SN 3001A and Below) ..............
6-5. IF Section, Top View (SN 3004A and Above) ..............
6-6. IF Section, Front View .......................
6-7. IF Section, Bottom View .......................
3-111
3-113
3-114
3-115
3-117
3-118
3-119
3-121
3-122
3-123
3-124
3-126
3-126
3-127
3-128
3-131
3-132
3-135
3-135
3-136
3-136
3-138
3-140
3-142
3-144
3-145
3-147
3-148
3-150
3-151
3-153
3-154
3-156
3-157
3-158
3-159
3-161
3-163
4-2
4-6
4-9
4-12
4-18
5-2
6-4
6-5
6-6
6-7
6-8
6-9
6-10
Contents-6

Tables
2-l. Performance Test Cross-Reference ...................
2-2. Center Frequency Readout Error Test Record .............
2-3. Wide Span Error ..........................
2-4. Span Error .............................
2-5. Sweep Time Accuracy, Sweep Times 220 ms ..............
2-6. Sweep Time Accuracy, Sweep Times 220 s ...............
2-7. Sweep Time Accuracy, Sweep Times 220 ms (Alternate Procedure) ....
2-8. Bandwidth Accuracy ........................
2-9. Resolution Bandwidth Selectivity ...................
2-10. Bandwidth Switching Uncertainty ...................
2-11. Input Attenuator Switching Uncertainty ................
2-12. IF Gain Uncertainty, 10 dB Steps ...................
2-13. IF Gain Uncertainty, 2 dB Steps ...................
2-14. IF Gain Uncertainty, 0.1 dB Steps ..................
2-15. Log Scale Switching Uncertainty ...................
2-16. Log Amplitude Fidelity .......................
2-17. Linear Amplitude Fidelity ......................
2-18. Fast Sweep Time Accuracy (<20 ms) .................
2-19. Wide Span Error, Step 7, 9, and 11 ..................
2-20. Span Error, Step 12 .........................
3- 1. Adjustment Cross Reference .....................
3-2. Adjustable Components .......................
3-3. Factory-Selected Components .....................
3-4. Standard Value Replacement Capacitors ................
3-5. Standard Value Replacement 0.125 Resistors ..............
3-6. Standard Value Replacement 0.5 Resistors ...............
3-5. Initial Adjustment Positions .....................
3-6. Initial Adjustment Positions .....................
3-7. Parts for Low-Noise DC Supply ....................
3-8. Crystal Filter Bypass Network Configuration for A4A4 and A4A8 (21.4 MHz)
3-9. Crystal Filter Bypass Network Configuration for A4A7 (3 MHz) .....
4-l. Impulse Bandwidth Accuracy .....................
4-2. 6 dB Resolution Bandwidth Accuracy .................
4-3. Impulse and Resolution Bandwidth Selectivity .............
4-4. Bandwidth Switching Uncertainty ...................
5-l. Log Amplitude Fidelity (10 Hz RBW; Option 857) ...........
5-2. Log Amplitude Fidelity (10 kHz RBW; Option 857) ...........
5-3. Linear Amplitude Fidelity . . . . . . . . . . . . . . . . . . . . . .
2-3
2-6
2-9
2-9
2-12
2-13
2-13
2-15
2-18
2-20
2-22
2-37
2-38
2-40
2-42
2-45
2-46
2-66
2-73
2-73
3-3
3-5
3-13
3-20
3-21
3-23
3-61
3-64
3-162
3-163
3-163
4-6
4-7
4-10
4-12
5-4
5-5
5-6
Contents-7

General Information
Introduction
This HP 8568B Tests and Adjustments Manual contains two sections: Performance Tests
and Adjustments Procedures. The Performance Tests provided should be performed for the
following reasons:
n If the test equipment for the Operation Verification Program is not available.
n If the instrument does not pass all of the Operation Verification tests.
n For complete verification of specifications not covered by the Operation Verification
program.
The adjustment procedures should be performed for the following reasons:
w If the results of a performance test are not within the specifications.
n After the replacement of a part or component that affects electrical performance.
Warning
The adjustment procedures require access to the interior of the instrument
and therefore should only be performed by qualified service personnel. There
are voltages at many points in the instrument which can, if contacted, cause
personal injury. Be extremely careful. Adjustments should be performed only
by trained service personnel.
Power is still applied to this instrument with the LINE switch in STANDBY.
There is no OFF position on the LINE switch. Before removing or installing any
assembly or printed circuit board, remove the power cord from the rear of both
instruments and wait for the MAINS indicators (red LEDs) to go completely out.
Capacitors inside the instrument may still be charged even if the instrument has
been disconnected from its source of power.
Use a non-metallic tuning tool whenever possible.
Instruments Covered by this Manual
This manual contains procedures for testing and adjusting HP 8568B Spectrum Analyzers,
including those with Option 001 (75 Ohm RF INPUT), Option 400 (400 Hz operation),
Option 462 (Impulse Bandwidths), and Option 857 installed. The procedures in this manual
can also be used to adjust HP 8568A Spectrum Analyzers that have been converted into HP
8568B Spectrum Analyzers through the installation of an HP 8568AB Retrofit Kit (formerly
HP 8568A+OlK Retrofit Kit).
General Information l-1